The invention relates to a unit for handling the remainder of optical cables wired in a device for mounting telecommunications equipment such as transmission devices, telephone switching devices and so on and to a method for wiring the optical cables using the unit for handling the remainder thereof.
The conventional units for handling the remainder thereof and cable supporting sections known are disclosed in JP-A-222866/1996, for example.
FIG. 1 is an exploded perspective view of construction of a telecommunication equipment unit-mounting device (hereafter, referred as a unit-mounting device) disclosed in the gazette above. FIG. 2 is an enlarged perspective view of construction of the conventional unit for handling the remainder of optical cables, the unit being arranged in the unit-mounting device shown in FIG. 1. FIG. 3 is an enlarged perspective view of construction of a wire saddle, which is used in the unit shown in FIG. 2 in order to keep hold of the optical cables.
In FIG. 1, a reference numeral 1 denotes a telecommunications equipment mounted unit mounting telecommunications equipment (not shown) such as transmission devices, telephone switching devices and so on, the equipment using optical cables as a means of conveying intelligence. A reference numeral 2 denotes a unit-mounting frame mounting the telecommunications equipment mounted unit 1 thereon. A reference numeral 3 denotes a box-shaped rack including an inner wall face having a mounting section 3a on which a plurality of unit-mounting frames 2 are mounted. A reference numeral 4 denotes a unit for handling the remainder of optical cables 5 used for transferring signals to the telecommunications equipment (not shown) mounted in the telecommunications equipment mounted unit 1 in order to install the optical cables 5 onto the unit 1.
As shown in FIG. 2, the unit 4 includes a rectangular, flat-shaped cable supporting section 4a for holding the loop-shaped remainder 5a of the optical cables 5 and a pair of supporting arms 4b extending from both sides of the cable supporting section 4a. Each front end of the supporting arms 4b is fixed on an upper face of one wall of the unit-mounting frames 2 to cantilever the cable supporting section 4a. Two rows of mounting holes 4c along the length of the cable supporting section 4a are formed at the cable supporting section 4a. A wire saddle 6 shown in FIG. 3 is fixed using a screw at the mounting hole 4c corresponding to a position where the remainder 5a of the optical cable 5 should be handled, of the mounting holes 4c scattered over the cable supporting section 4a. The wire saddle 6 is shaped like a letter U. The wire saddle 6 includes an approximately rectangular-shaped bottom section 6a, a pair of wall sections 6b, a pair of tilting sections 6c and a mounting hole 6d. The bottom section 6a has a flat face corresponding to the upper face of the cable supporting 4a. The wall sections 6b are so formed at both sides of the bottom section 6a as to extend upwardly from the both sides. The tilting sections 6c is formed by bending sharply upper sections of the wall sections 6b toward an upper space of the bottom section 6a. The mounting hole 6d is formed at a central section of the bottom section 6a and allows insertion of a screw (not shown) which is used for mounting the wire saddle 6 on the cable supporting section 4a through the mounting hole 4c. A gap 6e, which is defined between the tilting sections 6c of the wire saddle 6, has a dimension smaller than an outer diameter of the optical cable 5.
An operation will be explained hereafter.
Initially, plural unit-mounting frames 2 are mounted in the rack 3 from the front as to be stacked in multi-layers and accordingly the unit 1 is mounted on each of the unit-mounting frames 2. Next, the optical cables 5, which are tied in a bundle and supplied from above or beneath along rear and side faces of the rack 3, is installed onto the cable supporting section 4a of the unit 4 which is mounted on a rear face of the unit-mounting frames 2. On performing the installation of the optical cable, the wire saddles 6 are so fixed in the mounting hole 4c of the cable supporting section 4a that all of them are arranged on a circle. The remainder 5a of the loop-shaped optical cable 5 is held on the wire saddles 6 arranged on the circle. In this case, the optical cable 5 is pressed downwardly against ends of the tilting sections 6c in the gap 6e while the optical cable 5 is sliding on upper faces of the tilting sections 6c. At this time, the tilting sections 6c are further bent downwardly due to elastic deformation of the tilting section 6c with respect to the wall section 6b. In this way, the gap 6e, which is defined between the tilting sections 6c, is spread briefly and becomes to have a dimension larger than the outer diameter of the optical cable 5. Therefore, the optical cable 5 is mounted in a space enclosed by the wire saddle 6. The gap 6e just after the optical cable 5 is passed through becomes to have a dimension smaller than the outer diameter of the optical cable 5 because the tilting sections 6c return to original positions, respectively. Therefore, even if the optical cable 5 floats in the air, the optical cable 5 is held in the space enclosed by the wire saddle 6. Moreover, the optical cables 5 held by the wire saddle 6 are connected to optical connectors (not shown) arranged in the telecommunications equipment of the unit 1, and then the optical cables 5 are fixed in a state of putting them in order.
FIG. 4 is a perspective view of an alternative cable supporting section, which is used in the unit shown in FIG. 2. FIG. 5 is a perspective view of a state of holding the remainder of the optical cables using the wire saddle shown in FIG. 3 and the cable supporting section shown in FIG. 4. As shown in FIG. 4 and FIG. 5, with the alternative, three rows of mounting holes 4c along the length of the cable supporting section 4a are formed at the cable supporting section 4a. The central row of the mounting holes 4c is shifted by one-half of travel between the mounting holes 4c in a longitudinal direction of the cable supporting section 4a with respect to the external rows of the mounting holes 4c. Therefore, two mounting holes 4c adjacent to each other in the central row and two mounting holes 4c in the external rows close to the two mounting holes 4c of the central row are used for handling the remainder 5a of one optical cable 5. Moreover, as shown in FIG. 5, in the central row of the mounting holes 4c, two mounting holes 4c adjacent to each other, except for both ends of the central row of the mounting holes 4c, are used for handling two optical cables 5.
The conventional unit for handling the remainder of the optical cables is however constructed as described above. Therefore, the optical connector (not shown) connected to the optical cable 5 handled using the unit 4 is close to the telecommunications equipment of the unit 1, and is apart from the unit 4. Accordingly, it is difficult to perform insertion and removal of the optical cable into and from the optical connector (not shown).
Moreover, with the conventional unit for handling the remainder of the optical cables, handling the remainder 5a of the optical cables 5 connected to the optical connector on setting up the rack 3 must perform after handling during in-plant fabrication of the unit. The complicated handling results in a poor-workability.
Further, with the conventional unit for handling the remainder of the optical cables, since numerous wire saddles 6 must be mounted on the unit, it takes much time to mount the wire saddles 6. Accordingly, there is a poor-workability problem.
The invention was made to solve the foregoing problems. Accordingly, it is an object of the invention to provide a unit for handling the remainder of optical cables improving the workability of connecting an optical cable to an optical connector, which is arranged in the device for mounting telecommunication equipment including transmission devices, the telephone switching devices and so on using the optical cables as a means of conveying intelligence, and improving the workability of handling the remainder of the optical cable.
A unit for handling the remainder of optical cables according to the invention, comprises: a cable supporting section holding the remainder of the optical cables; and a connector for interface, arranged at a central section of the cable supporting section to hold ends of the optical cables. In this way, when the optical cables are wired, the optical cables are connected simply to the optical connector arranged at the central section of the cable supporting section. Therefore, it is possible to facilitate check of positions where the optical cables are connected and that of insertion of the optical cables into the optical connector. It is further possible to improve the efficiency of workability during field installation of telecommunications equipment-mounting devices.
With the above arrangement, the cable supporting section may include: a first area for holding previously the remainder of one optical cable during in-plant fabrication; and a second area for holding the remainder of the other optical cable connecting through the connector for interface to an end of the one optical cable held by the first area during field installation of optical cables. In this way, when the remainder of the one optical cable is held previously on the first area during in-plant fabrication performed in advance of the field installation, it is possible to focus on handling the remainder of the specified optical cable on the field installation. As a result, it is possible to eliminate work-site errors, to improve the efficiency of workability and to reduce time for working. Since optical cables arranged during in-plant fabrication of the unit is not complicated with optical cables arranged during field installation, it is possible to facilitate work such as maintenance and so on.
With the above arrangement, at least one cable holder holding individually the remainder of the optical cables may be arranged at the first and second areas of the cable supporting section respectively, and the cable holder may include a wire saddle holding the remainder of the optical cables in being inserted into and passed through the wire saddle; and a cable guide ensuring the shortest bending radius of the optical cables. In this way, it is possible to ensure that the remainder of the optical cables is handled without increasing transmission loss of the optical cables.
With the above arrangement, the wire saddle may be integrated with the cable guide to constitute the cable holder. In this way, since there is no need to handle individually parts constituting the cable holder, it is possible to reduce time for assembling the cable supporting section including work of inserting the optical cables into the wire saddle and to bring down the cost of work.
With the above arrangement, it may further comprise a cover element jacketing the cable holder, wherein at least one part of the cover element is transparent. In this way, it is possible to check the interior of the cable holder through the transparent portion of the cover. Therefore, it is possible to prevent the transmission loss of the optical cables from increasing as a result of the optical cables, which should be wired, being pinched between the cable holder and the cover.
With the above arrangement, the cable holder may be stacked in multi-layers. In this way, it is possible to improve the efficiency of occupancy of the remainder of the optical cables.
We further provide a method for wiring optical cables by placing a unit for handling the remainder of the optical cables, by placing the unit in telecommunications equipment mounting device using the optical cables as a means of conveying intelligence and keeps hold of the remainder of the optical cables on a horizontal face, comprising the steps of: constituting the unit including a cable supporting section holding the remainder of the optical cables; and a connector for interface, arranged on the cable supporting section to hold ends of the optical cables; constituting the cable supporting section including: a first area for holding previously the remainder of one optical cable during in-plant fabrication of the unit; and a second area for holding the remainder of the other optical cable connecting through the connector for interface to an end of the one optical cable held by the first area during field installation of optical cables; handling the remainder of the optical cables in the first area; and placing the unit handled in the previous step in the telecommunications equipment mounting device. In this way, it is possible to improve the efficiency of workability and the productivity of the telecommunications equipment-mounting device, as compared with the case of handling the remainder of the optical cables in the first area after placing the unit for handling the remainder of the optical cables in the telecommunications equipment-mounting device.